De novo implantation vs. upgrade cardiac resynchronization therapy: a systematic review and meta-analysis

Comparative Analysis of Response to Cardiac Resynchronisation Therapy Upgrades in Patients with Implantable Cardioverter-Defibrillators and Pacemakers

Introduction: The efficacy of de novo cardiac resynchronisation therapy (CRT) in patients with heart failure (HF), left ventricular systolic dysfunction (LVSD), and a broad QRS morphology is well established. However, the optimal stage for upgrading patients with existing pacemakers (PPMs) or implantable cardioverter-defibrillators (ICDs) and HF with high-burden right ventricular (RV) pacing remains uncertain. Thus, this multicentre retrospective analysis compared patients with pre-existing PPMs or ICDs who underwent CRT upgrades to investigate the appropriate stage for CRT implantation in these patients and to assess the validity of treating both PPM and ICD recipients under the same recommendation level in the current guidelines. Materials and Methods: A total of 151 participants underwent analysis in this study, comprising 93 upgrades to cardiac resynchronisation therapy with pacemaker (CRT-P) and 58 upgrades to cardiac resynchronisation therapy with defibrillator (CRT-D) across three centres in the UK. The aim of the study was to investigate the safety and efficacy of upgrading to CRT from an existing conventional pacemaker or an ICD in the context of high-burden RV pacing. The analysis was conducted separately for each group, assessing changes in echocardiographic parameters, functional New York Heart Association (NYHA) class, and procedure-related complications. Results: The PPM group had a higher percentage RVP burden compared to the ICD group. Post-upgrade, NYHA functional class and EF and LV volumes improved in both groups; however, the response to an upgrade from a pacemaker was greater compared to an upgrade from an ICD. Post-procedural complication risks were similar across the two subgroups but significantly higher compared to de novo implantation. Conclusions: Within the CRT-P subgroup, participants exhibited better responses than their CRT-D counterparts, evident both in echocardiographic improvements and clinical outcomes. Furthermore, patients with non-ischemic cardiomyopathy (NICM) were better responders than those with ischaemic cardiomyopathy. These findings suggest that international guidelines should consider approaching each subgroup separately in the future.

Long-term outcomes from upgrade to cardiac resynchronisation therapy in ischaemic versus non-ischaemic heart disease

BACKGROUND

Cardiac resynchronisation therapy (CRT) can be necessary in patients with chronic heart failure, who have already been provided with transvenous cardiac implantable electrical devices. Upgrade procedures revealed controversial results, while long-term outcomes regarding underlying Ischaemic- (ICM) or Non-Ischaemic heart disease (NICM) have yet to be described.

METHODS

The Mannheim Cardiac Resynchronisation Therapy Registry (MARACANA) was designed as a retrospective observational single-centre registry, including all CRT implantations from 2013-2021 (n = 459). CRT upgrades (n = 136) were retrospectively grouped to either ICM (n = 84) or NICM (n = 52) and compared for New York Heart Association classification (NYHA), paced QRS-width, left ventricular ejection fraction (LVEF), tricuspid annular plane systolic excursion (TAPSE) and other heart failure modification aspects in the long-term (59.3 ± 5 months).

RESULTS

Baseline-characteristics including paced QRS-width, upgrade indications or NYHA-classification were comparable for both groups (group comparison p>.05). The CRT upgrade improved NYHA (ICM: 2.98 ± 0.4 to 2.29 ± 0.7, NICM: 2.94 ± 0.5 to 2.08 ± 0.5) and the LVEF (ICM: 27.2 ± 6.6 to 38.25 ± 8.8, NICM: 30.2 ± 9.4 to 38.7 ± 13.8%) after five years, irrespective of underlying heart disease (each group p < .05, group comparison p>.05). Only ICM revealed significant improvements in TAPSE (15.9 ± 4.1 to 18.9 ± 4.1 mm) and narrowing of the paced QRS-width (185.4 ± 29 to 147.2 ± 16.3 ms) after five years (each p < .05).

CONCLUSIONS

Upgrade to CRT might improve heart failure symptoms and left-ventricular systolic function in the long-term, irrespective of underlying ischaemic or non-ischaemic heart disease.

Comparison of de novo implantation vs. upgrade cardiac resynchronisation therapy: a multicentre experience

BACKGROUND

The clinical safety and consequences of upgrade procedures compared with de novo cardiac resynchronisation therapy (CRT) implantation in heart failure remain unclear. The present study aimed to assess clinical and procedural consequences of patients undergoing CRT upgrade as compared to de novo CRT implantations.

METHODS

In this prospective cohort study, two subgroups were considered as the study population as (1) de novo group that CRT was considered on optimised medical treatment with heart failure of NYHA functional class from II to IV, left ventricular ejection fraction (LVEF) of ≤35%, and QRS width of >130 ms and (2) upgrade group including the patients with previously implantable cardioverter defibrillator (ICD) with the indications for upgrading to CRT. The two groups were compared regarding the changes in clinical outcome and echocardiography parameters.

RESULTS

The procedure was successful in 95.9% of patients who underwent CRT upgrade and 100% of those who underwent de novo CRT implantation. It showed a significant improvement in LVEF, severity of mitral regurgitation and NYHA functional classification, without any difference between the two study groups. Overall procedural related complications were reported in 10.8% and 3.8% (p = .093) and cardiac death in 5.4% and 2.5% (p = .360), respectively, with no overall difference in postoperative outcome between the two groups.

CONCLUSIONS

Upgrading to CRT is a safe and effective procedure regarding improvement of functional class, left ventricular function status and post-procedural outcome.

Phenogrouping and risk stratification of patients undergoing cardiac resynchronization therapy upgrade using topological data analysis

Choosing the optimal device during cardiac resynchronization therapy (CRT) upgrade can be challenging. Therefore, we sought to provide a solution for identifying patients in whom upgrading to a CRT-defibrillator (CRT-D) is associated with better long-term survival than upgrading to a CRT-pacemaker (CRT-P). To this end, we first applied topological data analysis to create a patient similarity network using 16 clinical features of 326 patients without prior ventricular arrhythmias who underwent CRT upgrade. Then, in the generated circular network, we delineated three phenogroups exhibiting significant differences in clinical characteristics and risk of all-cause mortality. Importantly, only in the high-risk phenogroup was upgrading to a CRT-D associated with better survival than upgrading to a CRT-P (hazard ratio: 0.454 (0.228-0.907), p = 0.025). Finally, we assigned each patient to one of the three phenogroups based on their location in the network and used this labeled data to train multi-class classifiers to enable the risk stratification of new patients. During internal validation, an ensemble of 5 multi-layer perceptrons exhibited the best performance with a balanced accuracy of 0.898 (0.854-0.942) and a micro-averaged area under the receiver operating characteristic curve of 0.983 (0.980-0.986). To allow further validation, we made the proposed model publicly available ( https://github.com/tokmarton/crt-upgrade-risk-stratification ).

Upgrade of right ventricular pacing to cardiac resynchronization therapy in heart failure: a randomized trial

BACKGROUND AND AIMS

De novo implanted cardiac resynchronization therapy with defibrillator (CRT-D) reduces the risk of morbidity and mortality in patients with left bundle branch block, heart failure and reduced ejection fraction (HFrEF). However, among HFrEF patients with right ventricular pacing (RVP), the efficacy of CRT-D upgrade is uncertain.

METHODS

In this multicentre, randomized, controlled trial, 360 symptomatic (New York Heart Association Classes II-IVa) HFrEF patients with a pacemaker or implantable cardioverter defibrillator (ICD), high RVP burden ≥ 20%, and a wide paced QRS complex duration ≥ 150 ms were randomly assigned to receive CRT-D upgrade (n = 215) or ICD (n = 145) in a 3:2 ratio. The primary outcome was the composite of all-cause mortality, heart failure hospitalization, or <15% reduction of left ventricular end-systolic volume assessed at 12 months. Secondary outcomes included all-cause mortality or heart failure hospitalization.

RESULTS

Over a median follow-up of 12.4 months, the primary outcome occurred in 58/179 (32.4%) in the CRT-D arm vs. 101/128 (78.9%) in the ICD arm (odds ratio 0.11; 95% confidence interval 0.06-0.19; P < .001). All-cause mortality or heart failure hospitalization occurred in 22/215 (10%) in the CRT-D arm vs. 46/145 (32%) in the ICD arm (hazard ratio 0.27; 95% confidence interval 0.16-0.47; P < .001). The incidence of procedure- or device-related complications was similar between the two arms [CRT-D group 25/211 (12.3%) vs. ICD group 11/142 (7.8%)].

CONCLUSIONS

In pacemaker or ICD patients with significant RVP burden and reduced ejection fraction, upgrade to CRT-D compared with ICD therapy reduced the combined risk of all-cause mortality, heart failure hospitalization, or absence of reverse remodelling.

Special Issue: Latest Advances in Delivery and Outcomes of Cardiac Resynchronization Therapy and Conduction System Pacing

Cardiac Resynchronization Therapy (CRT) is an established technique to improve morbidity and mortality in selected heart failure patients [...].

Severe sleep apnea as a predictor of failure to respond to cardiac resynchronization therapy

BACKGROUND

The response to cardiac resynchronization therapy (CRT) is suboptimal in one-third of patients.

OBJECTIVES

The study aimed to evaluate the impact of sleep-disordered breathing (SDB) on the CRT-induced left ventricular (LV) reverse remodeling and response for CRT in patients with ischemic congestive heart failure (CHF).

METHODS

A total of 37 patients aged 65.43 years (SD 6.05), seven of whom were females, were treated with CRT according to class I European Society of Cardiology recommendations. Clinical evaluation, polysomnography, and contrast echocardiography were performed twice during the six-month follow-up (6M-FU) to assess the effect of CRT.

RESULTS

In 33 patients (89.1%), sleep-disordered breathing (SDB), predominantly central sleep apnea (70.3%) was observed. This include nine patients (24.3%) with an apnea-hypopnea index (AHI) of >30 events/hour. During the 6M-FU, 16 patients (47.1%) responded to CRT by reducing LV end-systolic volume index (LVESVi) by ≥15%. We stated a directly proportional linear relationship between AHI value and LV volume: LVESVi p = 0.004, and LV end-diastolic volume index p = 0.006.

CONCLUSIONS

Pre-existing severe SDB can impair the LV volumetric response to CRT even in an optimally selected group with class I indications for resynchronization, which may have an impact on long-term prognosis.

Baseline clinical characteristics of heart failure patients with reduced ejection fraction enrolled in the BUDAPEST-CRT Upgrade trial

AIMS

The BUDAPEST-CRT Upgrade study is the first prospective, randomized, multicentre clinical trial investigating the outcomes after cardiac resynchronization therapy (CRT) upgrade in heart failure (HF) patients with intermittent or permanent right ventricular (RV) pacing with wide paced QRS. This report describes the baseline clinical characteristics of the enrolled patients and compares them to cohorts from previous milestone CRT studies.

METHODS AND RESULTS

This international multicentre randomized controlled trial investigates 360 patients having a pacemaker (PM) or implantable cardioverter defibrillator (ICD) device for at least 6 months prior to enrolment, reduced left ventricular ejection fraction (LVEF ≤35%), HF symptoms (New York Heart Association [NYHA] functional class II-IVa), wide paced QRS (&gt;150 ms), and ≥20% of RV pacing burden without having a native left bundle branch block. At enrolment, the mean age of the patients was 73 ± 8 years; 89% were male, 97% were in NYHA class II/III functional class, and 56% had atrial fibrillation. Enrolled patients predominantly had conventional PM devices, with a mean RV pacing burden of 86%. Thus, this is a patient cohort with advanced HF, low baseline LVEF (25 ± 7%), high N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels (2231 pg/ml [25th-75th percentile 1254-4309 pg/ml]), and frequent HF hospitalizations during the preceding 12 months (50%).

CONCLUSION

When compared with prior CRT trial cohorts, the BUDAPEST-CRT Upgrade study includes older patients with a strong male predominance and a high burden of atrial fibrillation and other comorbidities. Moreover, this cohort represents an advanced HF population with low LVEF, high NT-proBNP, and frequent previous HF events.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov NCT02270840.

The Prognostic Value of Anemia in Patients with Preserved, Mildly Reduced and Recovered Ejection Fraction

Data on the relevance of anemia in heart failure (HF) patients with an ejection fraction (EF) > 40% by subgroup-preserved (HFpEF), mildly reduced (HFmrEF) and the newly defined recovered EF (HFrecEF)-are scarce. Patients with HF symptoms, elevated NT-proBNP, EF ≥ 40% and structural abnormalities were registered in the HFpEF-HFmrEF database. We described the outcome of our HFpEF-HFmrEF cohort by the presence of anemia. Additionally, HFrecEF patients were also selected from HFrEF patients who underwent resynchronization and, as responders, reached 40% EF. Using propensity score matching (PSM), 75 pairs from the HFpEF-HFmrEF and HFrecEF groups were matched by their clinical features. After PMS, we compared the survival of the HFpEF-HFmrEF and HFrecEF groups. Log-rank, uni-and multivariate regression analyses were performed. From 375 HFpEF-HFmrEF patients, 42 (11%) died during the median follow-up time of 1.4 years. Anemia (HR 2.77; 95%CI 1.47-5.23; p < 0.01) was one of the strongest mortality predictors, which was also confirmed by the multivariate analysis (aHR 2.33; 95%CI 1.21-4.52; p = 0.01). Through PSM, the outcomes for HFpEF-HFmrEF and HFrecEF patients with anemia were poor, exhibiting no significant difference. In HFpEF-HFmrEF, anemia was an independent mortality predictor. Its presence multiplied the mortality risk in those with EF ≥ 40%, regardless of HF etiology.

Long-term clinical outcomes after upgrade to resynchronization therapy: A propensity score-matched analysis

Background

Upgrade to cardiac resynchronization therapy (CRT) is common in Europe, despite little and conflicting evidence.

Objective

To compare long-term clinical outcomes in a cohort of patients receiving de novo or upgrade to CRT.

Methods

Single-center retrospective study of 295 consecutive patients submitted to CRT implantation between 2007 and 2018. Upgraded and de novo patients complying with a dedicated follow-up protocol were compared in terms of clinical (NYHA class improvement without major adverse cardiac events [MACE] in the first year of follow-up) and echocardiographic (left ventricle end-systolic volume reduction of >15% during the first year) response.

Results

No differences in the rate of clinical (59.3% vs 62.6%, P = .765) or echocardiographic response (72.2% vs 71.9%, P = .970) between groups were observed. Device-related complications were also comparable between groups (8.9% vs 8.4%, P = .892). Occurrence of MACE and all-cause mortality were analyzed over a median follow-up of 3 (interquartile range 1–6) years: MACE occurred less frequently in the de novo group (hazard ratio [HR]: 0.55, 95% confidence interval [CI]: 0.34–0.90, P = .018), but all-cause mortality was similar among groups (HR: 0.87, 95% CI: 0.46–1.64, P = .684). Propensity score–matching analysis was performed to adjust for possible confounder variables. In the propensity-matched samples, all-cause mortality (HR: 1.26, 95% CI: 0.56–2.77, P = .557) and MACE (HR: 0.84, 95% CI: 0.46–1.54, P = .574) were comparable between upgrade and de novo patients.

Conclusion

Survival after upgrade to resynchronization therapy was comparable to de novo implants. Additionally, clinical and echocardiographic response to CRT in upgraded patients were similar to de novo patients.

Trends in Cardiovascular Implantable Electronic Device Insertion Between 1988 and 2018 in Olmsted County

OBJECTIVES

This study sought to describe trends in cardiovascular implantable electronic device (CIED) insertion over the past 3 decades in Olmsted County.

BACKGROUND

Trends in CIED insertion in the United States have not been extensively studied.

METHODS

The Rochester Epidemiology Project is a medical records linkage system comprising the records of all residents of Olmsted County from 1966 to the present. CIED insertion between 1988 and 2018 was determined using International Classification of Diseases-Ninth Revision, International Classification of Diseases-10th Revision, and Current Procedural Terminology codes. Age- and sex-adjusted incidence rates, adjusted to the 2010 US White population, were calculated. Trends in incidence over time, across age groups, and between sex are estimated using Poisson regression models.

RESULTS

The age- and sex-adjusted incidence of device implants for the study period were as follows: overall CIED: 82.4 (95% CI: 79.2-85.6); permanent pacemaker (PPM): 62.9 (95% CI: 60.0-65.7); implantable cardioverter-defibrillator (ICD): 14.0 (95% CI: 12.6-15.3); and cardiac resynchronization therapy (CRT): 5.6 (95% CI: 4.7-6.4) per 100,000 per year. The overall incidence of CIED insertion increased between 1988 to 1993 and 2000 to 2005 and then decreased between 2000 to 2005 and 2012 to 218 (P < 0.0001). PPM and ICD insertion incidence followed these trends, whereas the incidence of CRT insertion increased between 2000 to 2005 and 2012 to 2018. CIED insertion incidence increased with age (P < 0.0001). CIED insertion incidence was greater in men (116.3 vs 57.3 per 100,000 per year in men vs women; P < 0.0001). The overall survival of CRT recipients improved (P = 0.0044).

CONCLUSIONS

The incidence values for PPM and ICD implants are decreasing, while the incidence of CRT implants is increasing. CIEDs are increasingly inserted in the elderly, men, and patients with higher comorbidities.

Comparison of de novo versus upgrade cardiac resynchronisation therapy on clinical effect and long-term outcome

BACKGROUND

The benefit of de novo cardiac resynchronisation therapy (CRT) implantation in selected patients with heart failure is well known. The number of upgrade procedures is increasing but data on clinical response and outcome are less well documented as compared to de novo implantation.

OBJECTIVES

To investigate the efficacy and outcome of CRT upgrade procedures in patients with existing cardiac implantable electronic devices (CIEDs).

METHODS

Baseline characteristics, change in New York Heart Association (NYHA) functional class, echocardiographic parameters, life-threatening ventricular tachyarrhythmias, all-cause mortality and mode of death were evaluated in CRT patients with the comparison between de novo and upgrade CRT procedures.

RESULTS

About 410 patients (CRT upgrade/de novo CRT, n = 97/313) were followed for 63.5 ± 38.1 months. Upgrade patients were older (75.5 ± 8.1 vs 69.9 ± 10.7 years; p < 0.001), had more often an ischaemic cause of heart failure (58.8% vs 45.4%; p = 0.021), a higher NYHA functional class (p = 0.004) and a higher comorbidity burden. Improvement in left ventricular ejection fraction (LVEF) was higher in the de novo CRT group (8.4 ± 9.9 vs 11.0 ± 10.3%; p = 0.035). Clinical response was similar between both groups (60.5 vs 62.5%; p = 0.793), as was mortality at 1 year (8.2 vs 5.8%; p = 0.351) and at last follow-up (33.0 vs 28.8%; p = 0.447). The proportion of cardiovascular related deaths was similar between both groups (46.9% vs 38.9%; p = 0.531).

CONCLUSIONS

Patients with CRT upgrade procedures have similar symptomatic improvements, as well as 1 year and long-term outcome as compared to patients with de novo CRT implantation.

Upgrade from implantable cardioverter-defibrillator vs. de novo implantation of cardiac resynchronization therapy: long-term outcomes

AIMS

To assess and compare long-term mortality and predictors thereof in de novo cardiac resynchronization therapy defibrillators (CRT-D) vs. upgrade from an implantable cardioverter-defibrillator (ICD) to CRT-D.

METHODS AND RESULTS

Study population consisted of 595 consecutive patients with CRT-D implanted between 2002 and 2015 in a tertiary care, university hospital, in a densely inhabited, urban region of Poland [480 subjects (84.3%) with CRT-D de novo implantation; 115 patients (15.7%) upgraded from ICD to CRT-D]. In a median observation of 1692 days (range 457-3067), all-cause mortality for de novo CRT-D vs. CRT-D upgrade was 35.5% vs. 43.5%, respectively (P = 0.045). On multivariable regression analysis including all CRT recipients, the previously implanted ICD was an independent predictor for death [hazard ratio (HR) 1.58, 95% confidence interval (CI) 1.10-2.29, P = 0.02]. For those, who were upgraded from ICD to CRT-D, the independent predictors for all-cause death were as follows: creatinine level (HR 1.01, 95% CI 1.00-1.02, P = 0.01), left ventricular end-systolic diameter (HR 1.07, 95% CI 1.02-1.11, P = 0.002), New York Heart Association (NYHA) IV class at baseline (HR 2.36, 95% CI 1.00-5.53, P = 0.049) and cardiac device-related infective endocarditis during follow-up (HR 2.42, 95% CI 1.02-5.75, P = 0.046). A new CRT scale (Creatinine ≥150 μmol/L; Remodelling, left ventricular end-systolic ≥59 mm; Threshold for NYHA, NYHA = IV) showed high prediction for mortality in CRT-D upgrades (AUC 0.70, 95% CI 0.59-0.80, P = 0.0007).

CONCLUSION

All-cause mortality in patients upgraded from ICD is significantly higher compared with de novo CRT-D implantations and reaches almost 45% within 4.5 years. A new CRT scale (Creatinine; Remodelling; Threshold for NYHA) has been proposed to help survival prediction following CRT upgrade.

Long-term survival following upgrade compared with de novo cardiac resynchronization therapy implantation: a single-centre, high-volume experience

AIMS

Patients with a pacemaker or implantable cardioverter-defibrillator are often considered for cardiac resynchronization therapy (CRT). However, limited comprehensive data are available regarding their long-term outcomes.

METHODS AND RESULTS

Our retrospective registry included 2524 patients [1977 (78%) de novo, 547 (22%) upgrade patients] with mild to severe symptoms, left ventricular ejection fraction ≤35%, and QRS ≥ 130ms. The primary outcome was the composite of all-cause mortality, heart transplantation (HTX), or left ventricular assist device (LVAD) implantation; secondary endpoints were death from any cause and post-procedural complications. In our cohort, upgrade patients were older [71 (65-77) vs. 67 (59-73) years; P < 0.001], were less frequently females (20% vs. 27%; P = 0.002) and had more comorbidities than de novo patients. During the median follow-up time of 3.7 years, 1091 (55%) de novo and 342 (63%) upgrade patients reached the primary endpoint. In univariable analysis, upgrade patients exhibited a higher risk of mortality/HTX/LVAD than the de novo group [hazard ratio (HR): 1.41; 95% confidence interval (CI): 1.23-1.61; P < 0.001]. However, this difference disappeared after adjusting for covariates (adjusted HR: 1.12; 95% CI: 0.86-1.48; P = 0.402), or propensity score matching (propensity score-matched HR: 1.10; 95% CI: 0.95-1.29; P = 0.215). From device-related complications, lead dysfunction (3.1% vs. 1%; P < 0.001) and pocket infections (3.7% vs. 1.8%; P = 0.014) were more frequent in the upgrade group compared to de novo patients.

CONCLUSION

In our retrospective analysis, upgrade patients had a higher risk of all-cause mortality than de novo patients, which might be attributable to their more significant comorbidity burden. The occurrence of lead dysfunction and pocket infections was more frequent in the upgrade group.

Upgrading to cardiac resynchronisation therapy: Concordance of real-world experience with clinical guidelines

Objective

Revision to cardiac resynchronisation therapy (CRT) in patients with existing pacemakers with worsening heart failure (HF) can improve symptoms and cardiac function. We identify factors that predict improvement in left ventricular ejection fraction (LVEF) within a year of CRT revision.

Methods

We performed a retrospective study of 146 consecutive patients (16% female, mean age 73 ± 11 years, mean LVEF 27 ± 8%) undergoing revision to CRT (January 2012 to May 2018) in a single tertiary centre. LVEF was measured pre-revision and 3, 6 and 12 months post-upgrade.

Results

At 6 months, 68% of patients demonstrated improvement in LVEF (mean ΔLVEF + 6.7% ± 9.6). Compared to patients in atrial fibrillation (AF), patients with sinus rhythm had a greater improvement in LVEF at 6 months (sinus 8.4 ± 10.3% vs. AF 4.2 ± 8.0%, p = 0.02). Compared to ischaemic cardiomyopathy (ICM), patients with non-ischaemic cardiomyopathy (NICM) had a greater improvement in LVEF at 6 months (NICM 8.4 ± 9.8% vs ICM 4.8 ± 9.2%, p = 0.05). Patients with RV pacing ≥40% at baseline had a greater improvement in LVEF at 6 months (≥40% RV pacing 9.3 ± 10.2 vs. < 40% RV pacing 4.0 ± 7.4%, p = 0.01). All improvements were sustained over 12 months post-revision. There was no significant difference between genders, years between initial implant and revision, or previous device type.

Conclusions

Our real-world experience supports current guidelines on CRT revision. NICM, ≥40% RV pacing and sinus rhythm are the main predictors of improvement in LVEF in patients who underwent CRT revision.

Predictors of response to cardiac resynchronization therapy in patients with chronic right ventricular pacing

Background

The benefits of de novo cardiac resynchronization therapy (CRT) in patients with QRS-prolongation and impaired left-ventricular function (LVEF) are well established. Current guidelines also recommend CRT-upgrade in patients requiring permanent or frequent right ventricular pacing (RVP) with symptomatic heart failure and reduced LVEF. Whereas several predictors of response to de novo CRT-implantation such as female gender, QRS-duration, non-ischemic cardiomyopathy (NICM) are known due to large prospective trials, similar factors regarding CRT-upgrade are currently lacking.

Methods and results

We examine 114 patients 3–6 months after CRT-upgrade due to frequent RVP (> 50%) and symptomatic heart failure. Response to CRT was evaluated by improvement in NYHA class referring to the Minnesota Living With Heart Failure Questionnaire. Only cardiomyopathy type and use of Angiotensin-converting-enzyme (ACE) inhibitor had an impact on response to CRT-upgrade in a linear regression model. Patients with NICM presented a greater responder rate than patients with ischemic cardiomyopathy (ICM) (80.4 vs. 60.3%, p < 0.05). Other traditional response predictors in de novo CRT recipients (e.g. QRS-width, female gender) showed no effect on CRT-response in this cohort.

Conclusion

Only underlying heart disease (NICM vs. ICM) and the use of ACE inhibitor were significant predictors of response to CRT-upgrade. In contrast to de novo CRT-recipients, where pre-implant QRS-duration is a key predictor, QRS-duration during RV-pacing has no significant impact on CRT-response in this cohort.

Graphic abstract

Comparative Analysis of Procedural Outcomes and Complications Between De Novo and Upgraded Cardiac Resynchronization Therapy

OBJECTIVES

This study compared rates of procedural success and complications between de novo cardiac resynchronization therapy (CRT) implantation versus upgrade, including characterization of technical challenges.

BACKGROUND

CRT upgrade is common, but data are limited on the incidence of procedural success and complications as compared to de novo implantation.

METHODS

All patients who underwent a transvenous CRT procedure at a single institution between 2013 and 2018 were reviewed for procedure outcome, 90-day complications, reasons for unsuccessful left ventricular lead delivery, and the presence of venous occlusive disease (VOD) that required a modified implantation technique.

RESULTS

Among 1,496 patients, 947 (63%) underwent de novo implantation and 549 (37%) underwent device upgrade. Patients who received a device upgrade were older (70 ± 12 years vs. 68 ± 13 years; p < 0.01), with a male predominance (75% vs. 66%; p < 0.01) and greater prevalence of comorbidities. There was no difference in the rate of procedural success between de novo and upgrade CRT procedures (97% vs. 96%; p = 0.28) or 90-day complications (5.1% vs. 4.6%; p = 0.70). VOD was present in 23% of patients who received a device upgrade and was more common among patients with a dual-chamber versus a single-chamber device (26% vs. 9%; p < 0.001). Patients with and without VOD had a similar composite outcome of procedural failure or complication (8.0% vs. 7.8%; p = 1.0).

CONCLUSIONS

Rates of procedural success and complications were no different between de novo CRT implantations and upgrades. VOD frequently increased procedural complexity in upgrades, but alternative management strategies resulted in similar outcomes. Routine venography before CRT upgrade may aid in procedural planning and execution of these strategies.

Comparison of left ventricular lead upgrade vs continued medical care among patients eligible for cardiac resynchronization therapy at the time of defibrillator generator replacement: Predictors of left ventricular lead upgrade and associations with long-term outcomes

BACKGROUND

Randomized trials evaluating cardiac resynchronization therapy (CRT) have excluded patients with a pre-existing implantable cardioverter-defibrillator (ICD). The association of CRT upgrade with clinical outcomes in patients with a pre-existing ICD is unclear.

OBJECTIVE

The purpose of this study was to examine a CRT-eligible population to evaluate clinical outcomes associated with CRT upgrade compared to patients who did not undergo CRT.

METHODS

Using the National Cardiovascular Data Registry (NCDR) ICD Registry between April 2010 and December 2014, we created a hierarchical logistic regression model to identify predictors of CRT upgrade in a CRT-eligible ICD population. In the subpopulation of patients with Medicare-linked claims data, differential outcomes were determined with censoring at 3 years. The primary endpoint of this study was all-cause mortality, with secondary endpoints of rates of hospitalization and procedural complications.

RESULTS

CRT upgrade was performed in 75.5% of CRT-eligible patients with pre-existing ICD (n = 15,803). Presence of left bundle branch block conduction was the strongest predictor of CRT upgrade (odds ratio [OR] 4.56; 95% confidence interval [CI] 4.08-5.11; P <.0001). In both unadjusted and adjusted analyses, CRT upgrade was associated with a reduction in mortality at 3 years (unadjusted hazard ratio [HR] 0.80; 95% CI 0.70-0.92; P = .001; adjusted HR 0.84; 95% CI 0.72-0.98; P = .02, respectively). Compared to patients with ICD generator replacement only, patients who underwent CRT upgrade experienced no different 3-year rates of hospitalization (adjusted HR 1.01; 95% CI 0.91-1.12; P = .81) or 1-year periprocedural complication rates (adjusted HR 1.07; 95% CI 0.79-1.45; P = .66).

CONCLUSION

In a national registry of CRT-eligible patients with pre-existing ICD, upgrade to CRT was associated with lower rates of mortality than continued medical management.

Survival of patients with pacing-induced cardiomyopathy upgraded to CRT does not depend on defibrillation therapy

BACKGROUND

Permanent right ventricular pacing (RVP) results in cardiac dyssynchrony that may lead to heart failure and may be an indication for the use of cardiac resynchronization therapy (CRT). The study aimed to evaluate predictors of outcomes in patients with pacing-induced cardiomyopathy (PICM) if upgraded to CRT.

METHODS

One hundred fifteen patients, 75.0 years old (IQR 67.0-80.0), were upgraded to CRT due to the decline in left ventricle ejection fraction (LVEF) caused by the long-term RVP. A retrospective analysis was performed using data from hospital and outpatient clinic records and survival data from the National Health System.

RESULTS

The prior percentage of RVP was 100.0% (IQR 97.0-100.0), with a QRS duration of 180.0 ms (IQR 160.0-200.0). LVEF at the time of the upgrade procedure was 27.0% (IQR 21.0-32.75). The mean follow-up was 980 ± 522 days. The primary endpoint, death from any cause, was met by 26 (22%) patients. Age > 82 years (HR 5.96; 95% CI 2.24-15.89; P = .0004) and pre-CRT implantation LVEF < 20% (HR 5.63; 95%CI 2.19-14.47; P = .0003), but neither the cardioverter-defibrillator (ICD) implantation (HR 1.00; 95%CI 0.45-2.22; P = 1.00), nor the presence of atrial fibrillation (HR 1.22; 95%CI 0.56-2.64; P = .62), were independently associated with all-cause mortality.

CONCLUSION

Advanced age and an extremely low LVEF, but neither the presence of atrial fibrillation nor implanting an additional high voltage lead, influence the all-cause mortality in patients after long-term RVP, when upgraded to CRT.

Long term outcomes in patients with chronic right ventricular pacing upgraded to cardiac resynchronization therapy

INTRODUCTION

In patients with chronic systolic heart failure and frequent right ventricular pacing (RVP), upgrade to cardiac resynchronization therapy (CRT) has become common practice despite a lack of randomized clinical trials. We aimed to evaluate long term outcomes in patients upgraded to CRT from chronic RVP compared with de novo CRT implants.

METHODS AND RESULTS

We reviewed medical charts on consecutive patients with a left ventricular ejection fraction (LVEF) ≤ 35% and a QRSd ≥ 120 ms undergoing CRT. Survival free of left ventricular assist device (LVAD) and a heart transplant was compared amongst patients on the basis of pre-CRT QRS morphology. Improvement in LVEF was also compared across groups. A total of 1260 patients met inclusion criteria of whom 233 were upgraded from chronic RVP. Over a mean follow up 6.5 ± 4.0 years there were 821 endpoints (27 LVAD, 30 heart transplants, and 764 deaths). In a multivariate Cox regression model, upgraded patients had worse outcomes (HR 1.3(1.1-1.7) P = .007) compared with those with native LBBB and similar outcomes to patients with non-LBBB(HR 0.96(0.76-1.21) P = .7). The survival curve for chronic RVP parallels native LBBB for approximately 2.5 years before dropping sharply. Patients with chronic RVP derive similar improvements in LVEF compared with those with LBBB and superior improvements compared with those with non-LBBB.

CONCLUSIONS

Despite achieving similar levels of LVEF improvement, patients with systolic heart failure with chronic RVP undergoing upgrade to CRT have inferior long term outcomes compared with patients with native LBBB. Long term outcomes with CRT in patients with chronic RVP, RBBB, and IVCD are similar.

Right ventricular mechanical pattern in health and disease: beyond longitudinal shortening

Right ventricular (RV) function has proven to be a prognostic factor in heart failure with reduced and preserved ejection fraction and in pulmonary hypertension. RV function is also a cornerstone in the management of novel clinical issues, such as mechanical circulatory support devices or grown-up congenital heart disease patients. Despite the notable amount of circumferentially oriented myofibers in the subepicardial layer of the RV myocardium, the non-longitudinal motion directions are often neglected in the everyday assessment of RV function by echocardiography. However, the complex RV contraction pattern incorporates different motion components along three anatomically relevant axes: longitudinal shortening with traction of the tricuspid annulus towards the apex, radial motion of free wall often referred as the "bellows effect", and anteroposterior shortening of the chamber by stretching the free wall over the septum. Advanced echocardiographic techniques, such as speckle-tracking and 3D echocardiography allow an in-depth characterization of RV mechanical pattern, providing better understanding of RV systolic and diastolic function. In our current review, we summarize the existing knowledge regarding RV mechanical adaptation to pressure- and/or volume-overloaded states and also other physiologic or pathologic conditions.

EHRA White Paper: knowledge gaps in arrhythmia management—status 2019

Clinicians accept that there are many unknowns when we make diagnostic and therapeutic decisions. Acceptance of uncertainty is essential for the pursuit of the profession: bedside decisions must often be made on the basis of incomplete evidence. Over the years, physicians sometimes even do not realize anymore which the fundamental gaps in our knowledge are. As clinical scientists, however, we have to halt and consider what we do not know yet, and how we can move forward addressing those unknowns. The European Heart Rhythm Association (EHRA) believes that scanning the field of arrhythmia / cardiac electrophysiology to identify knowledge gaps which are not yet the subject of organized research, should be undertaken on a regular basis. Such a review (White Paper) should concentrate on research which is feasible, realistic, and clinically relevant, and should not deal with futuristic aspirations. It fits with the EHRA mission that these White Papers should be shared on a global basis in order to foster collaborative and needed research which will ultimately lead to better care for our patients. The present EHRA White Paper summarizes knowledge gaps in the management of atrial fibrillation, ventricular tachycardia/sudden death and heart failure.

Complications associated with cardiac resynchronization therapy upgrades versus de novo implantations

INTRODUCTION

A significant number of patients undergo upgrade to cardiac resynchronization therapy (CRT). These patients tend to differ from individuals undergoing de novo CRT implantations both in terms of their baseline demographics and the etiology underlying their heart failure. Areas covered: There are several factors that need to be considered when upgrading patients to CRT, such as, venous patency. Potentially, these conditions can cause issues which may result in procedures being more difficult than de novo implantations. This article discusses these issues and compares the rates of procedural-related complications for CRT upgrades and de novo implantations. It discusses the proportion of patients that are likely to respond to CRT with each intervention. Expert commentary: Understanding the relative risks of CRT upgrades versus de novo implantations is important to help operators select the correct initial device and counsel patients accordingly. Growing experience with image-guided implantations and endocardial pacing may prove to be particularly relevant to patients undergoing CRT upgrades.

Upgrades from a previous device compared to de novo cardiac resynchronization therapy in the European Society of Cardiology CRT Survey II

BACKGROUND

To date, there are no data from randomized controlled studies on the benefit of cardiac resynchronization therapy (CRT) when implanted as an upgrade in patients with a previous device as compared to de novo CRT. In the CRT Survey II we compared the baseline data of patients upgraded to CRT (CRT-P/CRT-D) from a previous pacemaker (PM) or implantable cardioverter-defibrillator (ICD) to de novo CRT implantation.

METHODS AND RESULTS

In the European CRT Survey II, clinical practice data of patients undergoing CRT and/or ICD implantation across 42 European Society of Cardiology (ESC) countries were collected between October 2015 and December 2016. Out of a total of 11 088 patients, 2396 (23.2%) were upgraded from a previous PM or ICD and 7933 (76.8%) underwent de novo implantation. Compared to de novo implantations, upgraded patients were older, more often male, more frequently had ischaemic heart failure aetiology, atrial fibrillation, reduced renal function, worse heart failure symptoms, and higher N-terminal pro-B-type natriuretic peptide levels. Upgraded patients were more often PM-dependent and less frequently received CRT-D. Total peri-procedural, in-hospital complications and length of hospital stay were similar. Upgraded patients were less frequently treated with heart failure medication at discharge.

CONCLUSION

Despite a lack of evidenced-based data, close to one quarter of all CRT implantations across 42 ESC countries were upgrades from a previous PM or ICD. Despite older age and worse symptoms, the CRT implantation procedures in upgraded patients were equally frequently successful and complications similar to de novo implantations. These results call for more studies.